Sliding roof systems are known which have at least one guide rail, a carriage that is displaceable in the guide rail, a lifting mechanism that controls a displacement of the front edge of the cover, a raising mechanism that controls a displacement of the rear edge of the cover, and a transfer mechanism adapted to transfer a displacement of the carriage to the raising mechanism.
In its closed position, the cover of the sliding roof system seals an opening in the vehicle roof. In a simple example, the opening is rectangular and is provided in a roof skin made of sheet metal or a plastic material. Commonly used sliding roof systems allow the cover to be first raised outward at its rear edge, so that a so-called venting position is reached. In a further step, the front edge of the cover can then also be raised outward, so that when the cover has been lifted altogether, it is moved rearward and thereby exposes the opening to a greater or lesser extent.
As far as terms such as “front”, “rear”, “top”, “bottom” or “outside” are used here, they relate to the usual installation conditions of the sliding roof system in a motor vehicle which is in its usual operating position. The term “outside” refers to the perspective of a vehicle occupant.
The known sliding roof systems have various drawbacks. For one thing, the lifting mechanism restricts the headroom. This is critical in particular with regard to the head impact requirements, which are used to assess the loads possibly acting on the head of a vehicle occupant in the event of an accident. Also, in known sliding roof systems, detent elements are employed on various occasions, causing disturbing noises in the necessary final and intermediate positions. Furthermore, it is not possible in the systems employed today to adjust the cover relative to the mechanism in its overall width. These constraints frequently lead to tensions or distortion of the mechanism of the sliding roof system, which then results in reduced ease of movement. A further reason for the sliding roof system not moving smoothly when the cover is shifted may reside in that the system is overdetermined and/or unfavorable pairings of materials of the gliding system are used. Nowadays, the selection of surface materials that can be used for the guide rail is determined primarily by the manufacturing methods employed for producing the cover (in particular a glass cover). It has also been found that the known sliding roof systems each require a vehicle-specific adaptation to different curvatures and dimensions of the vehicle roof.
It is the object of the invention to provide a sliding roof system eliminating at least some of these drawbacks.